The traditional methods for breast cancer screening (physical examination and film screen mammography) suffer from poor specificity and difficulty in detection lesions in the radiographically dense breast. There has been intense interest in the development of better techniques to detect breast cancer which have led to the development of high resolution breast ultrasound, breast MRI and full field digital mammography. In addition, there has been great progress in understanding factors related to breast cancer risk and identifying individuals at high risk for breast cancer. This has led to efforts to test newer breast imaging techniques for detecting screening this population. This makes it difficult to even plan a large screening trial to show the effect of intensive high risk screening of cancer outcome. The hospital of the University of Pennsylvania is unique in that it has ongoing research efforts in nearly every breast imaging technology. In addition, there is a strong risk assessment group couple to a network of 40 hospitals from which patients may be recruited. This project is intended to study the use of multi-modality screening of high risk women in an effort to understand the relative merits of the different breast imaging technologies. It is expected that these efforts will be used to develop a phase 3 study of high risk breast cancer screening.